1. Field of the Invention
The present invention relates to a zipper and a slide zipper assembly for use in plastic bags of the type in which items, such as foodstuffs, may be stored.
2. Description of the Prior Art
Slide zipper assemblies for use with plastic bags are well known in the reclosable fastener art. Examples of conventional slide zipper assemblies can be found in U.S. Pat. Nos. 5,007,143, 5,008,971, 5,131,121 and 5,664,299.
Conventional slide zipper assemblies typically comprise a plastic zipper having two interlocking profiles and a slider for opening and closing the zipper. The slider straddles the zipper and has a separating finger at one end which is inserted between the profiles to force them apart as the slider is moved along the zipper in an opening direction. The other end of the slider is sufficiently narrow to force the profiles into engagement and close the zipper when the slider is moved along the zipper in a closing direction.
Recently, slide zipper assemblies which do not make use of a separating finger have been disclosed. For example, in U.S. Pat. No. 5,809,621, a slide zipper assembly is disclosed wherein one of the zipper profiles is provided with a pair of handles which cooperates with the slider. As the slider is moved in an opening direction, the handles are squeezed together to disengage the profiles. The slider is narrower at the closing end than at the opening end.
In U.S. Pat. No. 5,442,838, a slide zipper assembly is disclosed wherein the zipper profiles are engaged and disengaged by a "rolling action". This "rolling action" is described as being achieved through cooperation between flanges on the profiles and shoulders which project inwardly from the arms of the slider. The slider shoulders are shaped throughout the length of the slider for engagement with the flanges and have a greater spacing at the closing end of the slider than at the opening end. Thus, as with other prior art slide zipper assemblies, the closing end of the slider is narrower than the opening end.
Many prior art slide zipper assemblies, however, have often proven unsatisfactory. For example, some prior art slide zipper assemblies provide for inadequate interlocking of the zipper profiles, thereby resulting in leaking of the contents of the bag. Other prior art slide zipper assemblies do not function consistently, often failing to properly interlock the zipper or smoothly open and/or close the zipper. Yet other slide zipper assemblies are of a complex design and often difficult and expensive to manufacture.
It is, therefore, the object of the present invention to provide a unique and novel slide zipper assembly for use with plastic bags which overcomes the problems associated with the prior art as discussed above.